Function run_verify 

pub fn run_verify(
    mana_dir: &Path,
    id: &str,
) -> Result<Option<VerifyResult>, Error>

Run the verify command for a unit without closing it.

Loads the unit, resolves the effective timeout, spawns the verify command, and captures all output. Returns a structured VerifyResult.

If the unit has no verify command, returns Ok(None).